Anal cancer is now known to be caused by infection with the human papilloma virus (HPV), commonly known as the wart virus. This virus is associated with carcinoma of the cervix in women. Anal cancer tends to be common with increasing age, but other factors may increase these risks. Anal sex, smoking and weakened immune system due to HIV infection or drugs for organ transplants may all increase the chance of developing anal cancer, but many patients with anal cancer may not have been exposed to any of these risks.
These include rectal bleeding, a lump at the anus and anal pain. It is often very treatable but will require a course of chemo-radiotherapy and sometimes surgery.